Treatment of tissue volume with radiant energy

Abstract

Devices and methods for utilizing electromagnetic radiation and other forms of energy to treat a volume of tissue at depth are described. In one aspect, a device modulates the flux incident on surface tissue to control and vary the depth in the tissue at which an effective dose of radiant energy is delivered and, thereby, treat a specific volume of tissue. The methods and devices disclosed are used to perform various treatments, including treatments to relieve pain and promote healing of tissue.

1 . A device for treating a volume of tissue, comprising:
 a source of EMR configured to transmit EMR to a tissue surface;   a controller electrically connected to said EMR source and configured to provide at least one control signal to said EMR source;   wherein said EMR source is configured to emit at least a first level of flux and a second level of flux in response to said controller, said first and second levels of flux corresponding to first and second penetration depths below the surface of the tissue.   
   
   
       2 . The device of  claim 1 , wherein said controller includes a modulator in electrical communication with said EMR source to control said first and second levels of flux. 
   
   
       3 . The device of  claim 1 , further including a cooling surface for contacting said tissue surface, said cooling surface configured to cool said tissue when in contact with said tissue surface during operation of said device. 
   
   
       4 . The device of  claim 1 , further including a window configured to pass EMR. 
   
   
       5 . The device of  claim 4 , wherein said window further includes a cooling surface for contacting said tissue surface, said cooling surface configured to cool said tissue when in contact with said tissue surface during operation of said device. 
   
   
       6 . The device of  claim 4 , wherein said window has a radiation-passing area greater than approximately 49 cm 2 . 
   
   
       7 . The device of  claim 4 , wherein said window is configured to provide a variable radiation-passing area. 
   
   
       8 . The device of  claim 1 , further comprising an aperture configured to pass radiation to said tissue. 
   
   
       9 . The device of  claim 8 , wherein said aperture has an opening with a diameter greater than approximately 7 cm. 
   
   
       10 . The device of  claim 8 , wherein said aperture is configured to have a variable size. 
   
   
       11 . The device of  claim 1 , wherein said device is a handheld device. 
   
   
       12 . The device of  claim 1 , wherein said device is a consumer product. 
   
   
       13 . The device of  claim 1 , further comprising a feedback sensor configured to provide a feedback signal during operation;
 wherein said controller is electrically connected to said feedback sensor mechanism and configured to issue said control signals based on said information obtained from said feedback sensor.   
   
   
       14 . The device of  claim 13 , wherein said feedback sensor is a temperature sensor. 
   
   
       15 . The device of  claim 14 , wherein said temperature sensor is configured to measure the temperature of said tissue being treated during operation. 
   
   
       16 . The device of  claim 13 , wherein said feedback sensor is an optical Doppler sensor configured to measure the flow of blood within said tissue being treated. 
   
   
       17 . The device of  claim 1 , wherein said EMR source is configured to provide an input flux between approximately 0.1 and 10 watts/cm 2 . 
   
   
       18 . The device of  claim 1 , wherein the device is configured to have a total system power greater than 40 watts. 
   
   
       19 . The device of  claim 1 , wherein the device is configured to have a total system power greater than 80 watts. 
   
   
       20 . The device of  claim 1 , wherein said source is configured to provide a minimally effective dose of EMR to tissue depths up to approximately 50 mm. 
   
   
       21 . The device of  claim 1 , wherein said source is configured to provide a minimally effective dose of EMR to tissue depths up to approximately 20 mm. 
   
   
       22 . The device of  claim 1 , wherein said source is configured to provide a minimally effective dose of EMR to tissue depths up to approximately 10 mm. 
   
   
       23 . The device of  claim 1 , wherein said controller includes a memory device and a processor. 
   
   
       24 . The device of  claim 23 , further comprising input sensors, wherein said controller derives treatment parameters using input data from said input sensors. 
   
   
       25 . The device of  claim 23 , further comprising at least one feedback sensor in electrical communication with said controller, and wherein said controller is configured to compute at least one treatment parameter based on said sensor data. 
   
   
       26 . The device of  claim 1 , wherein said controller includes a lookup table containing information regarding treatment parameters. 
   
   
       27 . The device of  claim 1 , wherein said controller is configured to modulate said irradiance of EMR emitted from said source using intermittent pulses. 
   
   
       28 . The device of  claim 1 , wherein said source further includes optical elements configured to provide an adjustable area of EMR that is incident on a surface of said tissue. 
   
   
       29 . The device of  claim 1  wherein said EMR source is configured to emit a third level of flux in response to said at least one control signal, said third level of flux corresponding to a third depth below the surface of the tissue. 
   
   
       30 . A device for treating tissue, comprising:
 a source for generating EMR;   an optical window for contacting a surface of said tissue to be treated and for transmitting EMR from said source to said tissue;   a cooling system in thermal communication with said optical window, said cooling system configured to remove heat from said optical window; and   a modulator electrically connected to said EMR source for varying a radiant flux emitted by said EMR source from a first value corresponding to a first tissue depth to a second value corresponding to a second tissue depth.   
   
   
       31 . The device of  claim 30 , wherein said optical window is composed of sapphire. 
   
   
       32 . The device of  claim 30 , wherein said device is a handheld device. 
   
   
       33 . The device of  claim 30 , wherein said device is a consumer product. 
   
   
       34 . The device of  claim 30 , further comprising a feedback sensor in electrical communication with said modulator;
 wherein said modulator is configured to receive a feedback signal during operation and vary the flux emitted by said EMR source in response thereto.   
   
   
       35 . The device of  claim 34 , wherein said feedback sensor is a temperature sensor. 
   
   
       36 . The device of  claim 35 , wherein said temperature sensor is configured to measure the temperature of said tissue being treated. 
   
   
       37 . The device of  claim 35 , wherein said feedback sensor is an optical Doppler sensor configured to measure the flow of blood within said tissue being treated. 
   
   
       38 . The device of  claim 30 , wherein said source is configured to provide an input flux between approximately 0.1 and 10 watts/cm 2 . 
   
   
       39 . The device of  claim 30 , wherein said source is configured to irradiate tissue above a minimally effective threshold of irradiation at tissue depths selected from the group of ranges consisting of between approximately 0 and 50 mm, between approximately 0 and 20 mm, and between approximately 0 and 10 mm. 
   
   
       40 . The device of  claim 30 , wherein said modulator includes a memory device and a processor. 
   
   
       41 . The device of  claim 40 , further comprising at least one sensor in electrical communication with said modulator, wherein said modulator is configured to computes treatment parameters using signals from each of said at least one sensor. 
   
   
       42 . The device of  claim 30 , wherein said modulator includes a lookup table containing information regarding treatment parameters. 
   
   
       43 . The device of  claim 30 , wherein said modulator is configured to modulate said irradiance of EMR emitted from said source using intermittent pulses. 
   
   
       44 . The device of  claim 30 , wherein said optical window comprises an area greater than approximately 49 cm 2 . 
   
   
       45 . The device of  claim 30 , wherein said source further includes optical elements configured to provide an adjustable area of EMR incident on a surface of said tissue. 
   
   
       46 . The device of  claim 30 , wherein said modulator is electrically connected to said EMR source and is configured to vary said radiant flux emitted by said EMR source to a third value corresponding to a third tissue depth. 
   
   
       47 . The device of  claim 30 , wherein said modulator is configured to vary said radiant flux within a continuous range. 
   
   
       48 . The device of  claim 30 , wherein said modulator is configured to vary said radiant flux to a set of discrete values. 
   
   
       49 . A device for transmitting light into tissue to treat damaged tissue or reduce pain, comprising:
 a housing having an EMR source and an aperture for allowing EMR generated by said source to pass through said housing to said tissue;   wherein said source is configured to generate a flux of EMR passing through said aperture that is greater than or equal to approximately 0.1 W/cm 2 .   
   
   
       50 . The device of  claim 49 , wherein said aperture has a diameter in the range of about 1 cm to about 15 cm. 
   
   
       51 . The device of  claim 49 , wherein said aperture has a diameter of at least about 7 cm. 
   
   
       52 . The device of  claim 49 , wherein said device is configured to produce a beam of EMR having a cross-sectional area in the range of about 10 cm 2  to about 100 cm 2 . 
   
   
       53 . The device of  claim 49 , wherein said device is configured to produce a beam of EMR having a cross-sectional area of at least approximately 49 cm 2 . 
   
   
       54 . The device of  claim 49 , wherein said device is configured to produce a beam of EMR having a diameter of at least about 7 cm. 
   
   
       55 . The device of  claim 49 , wherein said aperture is adjustable. 
   
   
       56 . The device of  claim 55 , wherein said aperture is adjustable from a first area configured to produce a first level of flux to a second area configured to produce a second level of flux. 
   
   
       57 . A device for transmitting light into tissue, comprising:
 a housing having a window;   an EMR source mounted within said housing;   a set of optical elements mounted within said housing and forming an optical path extending between said EMR source and said window;   wherein said optical elements are adjustable to alter a spot size of EMR emitted from said window to the surface of the tissue to alter the input flux at the surface of the tissue, and   wherein the flux of said EMR emitted through said window is greater than or equal to about 0.1 W/cm 2 .   
   
   
       58 . A device for treating tissue at a predetermined depth below the surface of the tissue comprising:
 a housing having a window;   an EMR source mounted within said housing, wherein said optical window allows EMR to pass through said housing to said tissue surface;   wherein said EMR source provides a level of flux corresponding to said predetermined depth and provides a power density of greater than or equal to about 0.1 watts/cm 2 .   
   
   
       59 . A method for irradiating tissue at depth, comprising:
 selecting a first input flux corresponding to a first tissue depth; and   irradiating the tissue at said first depth using said first input flux.   
   
   
       60 . The method of  claim 59 , wherein the step of irradiating further includes irradiating at a level that is above a minimum threshold of irradiance required to provide at least a minimally effective dose of EMR. 
   
   
       61 . The method of  claim 59 , wherein the step of irradiating further includes irradiating at a level that is below a maximum threshold of irradiance required to provide at least a minimally effective dose of EMR. 
   
   
       62 . The method of  claim 59 , wherein the step of irradiating further includes irradiating at a level that is above a minimum threshold of irradiance required to provide at least an effective dose of EMR and below a maximum threshold of irradiance required to provide at least an effective dose of EMR. 
   
   
       63 . A method for treating a volume of tissue, comprising;
 irradiating a surface of said tissue with EMR having a first power density; and   irradiating said surface with EMR having a second power density, wherein said first and second power densities correspond to a location of said volume of tissue to be treated.   
   
   
       64 . The method of  claim 63  further, comprising modulating between said first and second power densities according to a time varying function. 
   
   
       65 . The method of  claim 64 , wherein said function is a continuous curve. 
   
   
       66 . The method of  claim 63 , further comprising modulating between said first and second power densities by irradiating tissue at a set of discrete interim power densities. 
   
   
       67 . The method of  claim 63 , further comprising modulating between said first and second power densities such that an applied power density remains above a minimum threshold of power densities that provide an effective dose of EMR to tissue at depth. 
   
   
       68 . The method of  claim 63 , further comprising modulating between said first and second power densities such that an applied power density remains below a minimum threshold of power densities that provide an effective dose of EMR to tissue at depth.